Release Notes

UM Version 6.11.1

The most significant update to UM version 6.11.1 is a set of performance improvements to the Persistent Store daemon. Some performance improvements were also applied to the data receive path for applications.

Attention
  See Deprecations for 6.11.1 for important information regarding future platform support for UM daemons.
  There are some special upgrade instructions for UM versions 6.10 and beyond that will affect a small percentage of users upgrading from pre-6.10 versions of UM. See Special Upgrade Instructions for 6.10. For general upgrade instructions, see Upgrade Procedure. You are also advised to inspect the full list of Deprecations.

# Enhancements for 6.11.1 <-

## Streaming Enhancements for 6.11.1 <-

The following new features and enhancements apply to UMS, UMP, and UMQ products.

- Performance improvements made to the data reception code paths, including reduction in calls to gettimeofday(), and some localized code optimizations.

## Persistence Enhancements for 6.11.1 <-

The following new features and enhancements apply to UMP and UMQ products.

- The Persistent Store benefits from the performance enhancements made on the data receive path. (See also Persistence Fixed Problems and Limitations for 6.11.1.)

## Queuing Enhancements for 6.11.1 <-

The following new features and enhancements apply to the UMQ product.

- None.

## Dynamic Router Enhancements for 6.11.1 <-

The following new features and enhancements apply to the Dynamic Routing Option (DRO).

- None.

# Fixed Problems and Limitations for 6.11.1 <-

## Streaming Fixed Problems and Limitations for 6.11.1 <-

The following bug fixes apply to UMS, UMP, and UMQ products.

Change Request | Description
--- | ---
10385, 10280 | Enhancement: Reduced number of gettimeofday() calls in context loop. This lowers receive-side latency and CPU load.

## Persistence Fixed Problems and Limitations for 6.11.1 <-

The following bug fixes apply to UMP and UMQ products.

Change Request | Description
--- | ---
10332, 10409 | FIXED: When the Persistent Store is configured to publish Daemon Statistics, there is a small chance that it will fail to initialize properly. It might log the error: `[CRITICAL]: Store-10184-80: umestore_dmon_publish: CoreApi-5688-2996: src must be valid` and could exit with a segmentation fault.
10400, 10401 | FIXED: Bug in Persistent Store leads to performance degradation over time. (This bug has existed in the Store for many years.)
10404, 10411 | FIXED: When using RPP with repository-type "disk", it is possible for a blocking receiver to get unrecoverable loss. This loss can be accompanied by the following warning in the Persistent Store log file: `[WARNING]: WARNING: failed assertion [ntohl(ohdr->sqn)==rec->sqn]`
10406, 10407 | FIXED: A bug fix added to 6.10.1 accidentally introduced a significant performance reduction in the UMP Persistent Store. This regression is repaired in 6.11.1.

## Queuing Fixed Problems and Limitations for 6.11.1 <-

The following bug fixes apply to the UMQ product.

- None.

## Dynamic Router Fixed Problems and Limitations for 6.11.1 <-

The following bug fixes apply to the Dynamic Routing Option (DRO).

- None.

# Special Upgrade Instructions for 6.11.1 <-

There are no upgrade instructions specific to 6.11.1. However, if you are upgrading from a version prior to 6.10, then you must examine the Special Upgrade Instructions for 6.10.

Also see Deprecations.